Alona

Sousa, Francisco Diogo Rocha & Elmoor-Loureiro, Lourdes Maria Abdu, 2019, Identification key for the Brazilian genera and species of Aloninae (Crustacea, Branchiopoda, Anomopoda, Chydoridae), Papéis Avulsos de Zoologia 59, pp. 1-16 : 9-10

of Alona sensu lato

1a Labral keel armed with 10-11 proximal short setulae, distalmost setae of fascicles not exceeding the level of the marginal denticles................. ............................... Alona elisae Sousa,Elmoor-Loureiro & Santos,2016

1b Labral keel armed with 2-4 proximal short setulae, distalmost setae of fascicles exceeding the level of the marginal denticles........................... .......................... Alona isabellae Sousa,Elmoor-Loureiro & Santos,2016

guttata -group of Alona sensu lato: Oval body, maximum height at middle body. Rostrum short, projected in lateral view; labral keel convex, a notch can be present, posterior margin with two clusters of short setulae. Posterior part of head shield triangular-shaped, three connected main head pores, tiny lateral head pores. Postabdomen with distalmost part truncated, anal and postanal margins almost parallel, preanal angle relatively prominent, 6-7 merged marginal denticles, basal spine developed. Six pairs of limbs; first limb with two setae on the first endite, Inner Distal Lobe (IDL) with three setae: first setae very short, setae 2-3 armed with setulae; exopodite of second limb armed with a seta relatively long; third limb with seven setae on the exopodite;fourth limb with six setae on the exopodite; exopodite of fifth limb bilobed, deep incursion between lobes, filter plate with three setae; sixth limb as a wide and elongated lobe.

Comments: Only a single species of the guttata -group of Alona sensu lato occurs in Brazil. It is considered a cosmopolitan species. It is likely that the Brazilian populations of this species in fact comprise a new, undescribed species.However, a broad revision including specimens from its type-region ( Norway) is still necessary to validate this statement. This group is morphologically well-defined and, thus, the creation of a new genus is also necessary. One species in Brazil, Alona cf. guttata Sars, 1862 .

Anthalona Van Damme, Sinev & Dumont, 2016 : Oval body, arched, carapace without denticle on the posteroventral corner. Rostrum short, projected in lateral view; labral keel with naked, with a notch or short denticles. Two connected main head pores, tiny lateral head pores with “Cosmarium” or lobed sacs underneath of them. Postabdomen relatively short,postanal part rounded,anal margin markedly concave, marginal denticles unmerged, distalmost setae of lateral fascicles long.Five pairs of limbs; first limb with three setae on the first endite, Inner Distal Lobe (IDL) with two setae armed with setulae or spines; exopodite of second limb naked or with a seta; third limb with six setae on the exopodite, fourth seta longer than others; fourth limb with six setae on the exopodite; exopodite of fifth limb with four setae, filter plate absent.

Comments: Except for A. neotropica Sousa Elmoor- Loureiro & Debastiani-Júnior, 2011, all species of this genus belong to the verrucosa -group of Alona sensu lato.